Interface system for an accessory and a communication device

ABSTRACT

A configurable interface system ( 100 ) couples an accessory ( 102 ) to a communication device ( 104 ). The interface system utilizes a memory device ( 120 ) embedded in the accessory ( 102 ) that stores physical configuration and event mapping descriptors ( 114, 122 ) pertaining to the accessory. The communication device ( 104 ) reads the physical configuration and event mapping descriptors and configures its external interface ( 112 ) in response thereto, preferably through the use of bi-directional GPIO lines ( 110 ).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is related to pending U.S. application Ser. No.10/669,033 by Higgins, et al. entitled “Audio Accessory OptimizationSystem” and U.S. application Ser. No. 10/669,034 by Ellis A. Pinder,entitled “Method and Apparatus To Self-Configure an Accessory Device,”both filed concurrently herewith, and assigned to Motorola, Inc.

TECHNICAL FIELD

This invention relates in general to accessories for communicationdevices, and more particularly to the interface between the accessoryand the communication device.

BACKGROUND

As portable electronic devices become smaller, there is a correspondingdecrease in the area for external device connectors commonly used foraccessories. There are also practical limits to external connectordensity and size, because such connectors are intended to be as durableand reliable as possible. Not only is the goal of a smaller connector inconflict with durability and reliability goals, but it also imposeslimits on the number of connector pins. Fewer connector pins limitsfunctionality and/or reduces flexibility.

Today's two-way radios connect to an array of accessories that are ofvarying complexity. Some of these accessories contain a microprocessorand are considered “smart”, while others are less complex (hereafter,“simple accessories”) and intended to be low cost. Smart accessoriestypically communicate with the radio through a data bus, while simpleaccessories tend to use a number of discrete digital lines and have nomicrocontroller. Smart accessories may also require discrete digitallines in addition to the data bus for special functions. Accessories mayoften have additional lines for audio, which further increases pincount. Although sophisticated digital interfaces are available that canhandle audio, data, and control signals, the cost and complexity of suchan interface is often prohibitive. A desired accessory interface must beflexible enough to meet the needs of both smart and simple accessorieswithout requiring excessive pin count, excessive cost, or excessivecomplexity.

Additionally, it is important to have a common accessory interface forall radio accessories, including accessories not yet developed. It isstrongly desired to minimize changes to the radio to support suchaccessories. Although some radios are intended to be flash-upgradeable,many lower-cost radios are not upgradeable. It is important thatlower-cost radios be able to utilize as many future accessories aspossible. It is also desirable for the least complicated or most simpleaccessories to work on the widest possible range of radios.

Accordingly, there is a need for a common accessory interface that meetsthe needs of both smart accessories and simple accessories, whileproviding maximum flexibility for configuring the interface. There isalso a need to keep the pin count of the accessory interface as small aspossible to minimize cost and complexity.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the present invention, which are believed to be novel,are set forth with particularity in the appended claims. The invention,together with further objects and advantages thereof, may best beunderstood by reference to the following description, taken inconjunction with the accompanying drawings, in the several figures ofwhich like reference numerals identify like elements, and in which:

FIG. 1 is an interface between an accessory and a portable communicationdevice in accordance with the present invention; and

FIG. 2 is a block diagram of radio software architecture formed inaccordance with a preferred embodiment of the invention; and

FIG. 3 is a radio and an external microphone accessory formed inaccordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

While the specification concludes with claims defining the features ofthe invention that are regarded as novel, it is believed that theinvention will be better understood from a consideration of thefollowing description in conjunction with the drawing figures, in whichlike reference numerals are carried forward.

In accordance with the present invention, there is provided herein acommunication device having a configurable external interface; anaccessory having a memory with both physical configuration and eventmapping descriptors pertaining to the accessory; and radio softwarecapable of reading the descriptors, configuring the external interface,and processing events related to the configurable interface.

The interface system of the present invention provides a highly flexiblemeans to interface accessories of varying complexity to a communicationdevice, preferably a portable communication device such as a two-wayradio, or a mobile radio. Simple accessories can now be affordedcapabilities not previously available or previously available only tosmart accessories. The present invention provides such increasedcapability with very minimal increase in cost. Accessories can now bedeployed with enhanced or altered capabilities with no change to theradio software or hardware.

FIG. 1 is a block diagram of an interface system 100 between anaccessory 102 and a portable communication device 104 in accordance witha preferred embodiment of the invention. In the preferred embodiment,the communication device 104 is a radio that contains a microcontroller106 with a configurable general purpose input output (GPIO) interface108. GPIO pins 110 with bi-directional capability—software programmableto function as either an input or an output—are connected to theexternal radio interface 112. Upon power-up of radio 104 the GPIO pins110 are configured to a default, inert configuration where all pins areconfigured as inputs. The default configuration is typically the resultof the power-up state of microcontroller 106. The radio 104 periodicallychecks the external radio interface 112 to detect the presence of anaccessory 102. Upon accessory detection, the radio 104 reads thecontents of embedded memory device 120. Embedded memory device 120 canbe any type of memory device, but those skilled in the art would likelyselect a memory device with a serial interface to minimize the pin countof external radio interface 112. Many different types of serial memorydevices are available, such as a single wire 1-Wire™ device from DallasSemiconductor, a two wire I²C™ device available from PhillipsElectronics, or a three wire Serial Peripheral Interface (SPI) memorydevice to name but a few. The serial interface provides bi-directionaldata and optionally clock signals to and from the serial memory device.In the preferred embodiment of the invention, the embedded memory device120 is a single wire memory device, such as the 1-Wire™ serial EEPROM.

The embedded memory device contains accessory configuration data 124which provides information to the radio 104 on how to configure externalaccessory interface 112 and how to operate accessory 102. Accessoryconfiguration data 124 contains exactly one accessory identifier 126, atleast one physical configuration descriptor 114 and at least one eventmapping descriptor 122. The accessory identifier 126 is used to uniquelyidentify the type or model of accessory 102.

To operate accessory 102, radio 104 must configure external radiointerface 112 and radio 104 must configure its software associated withinterface 112 to monitor and drive the appropriate signals in accordancewith the needs of the accessory. Before explaining the internal softwareconfiguration of radio 104 and its operation of interface 112, it isfirst necessary to explain how the configuration of interface 112 andthe aforementioned internal configuration of radio 104 is specified.This is accomplished by the physical descriptor(s) 114 and event mappingdescriptor(s) 122.

The radio will then read all the physical configuration descriptors 114.In the preferred embodiment, all port configuration information iscontained in a single physical configuration descriptor (PCD). Thephysical configuration descriptor contains the following informationabout each of the five GPIO lines:

Data direction: input or output;

Logic sense: active high or active low;

Priority (inputs only) high/low (high priority is typically assigned tointerrupt).

The radio 104 then configures the external radio interface 112 tocorrespond to the physical configuration descriptor. In the preferredembodiment, radio 104 supports a standard set of five GPIOs labeledGPIO0 to GPIO3 with GPIO4 not depicted in FIG. 1. In an alternateembodiment, a radio may support a smaller or larger set of GPIOs.Connection of an accessory that requires an extended set of GPIOs to aradio that only physically provides the standard five GPIOs would resultin an error condition. The radio 104 will detect the error condition byseeing a physical configuration descriptor 114 that specifies morephysical GPIO lines than are physically present on the radio. The radio104 indicates this error condition to the user and blocks the operationof the accessory 102. Alternately, radio 102 may allow operation of theaccessory with reduced functionality if the radio determines that suchoperation is possible. For example, suppose a low-cost radio supports 3GPIOs, and a high-tier radio support five GPIOs. A remote speakermicrophone (RSM) requires two GPIOs, but a “deluxe” RSM requires fourGPIOs to support an extra Emergency button and “man down” sensor. Thestandard RSM will work properly on both radios, because both radios canprovide the required number of GPIOs. The deluxe RSM will work properlyon the high tier radio, but the low tier radio has an insufficientnumber of lines. The radio manufacturer may choose to allow limitedoperation of the microphone with one of the functions unconfigured,perhaps man-down. Alternately, the radio manufacturer may choose todisallow operation of this microphone entirely for fear the user expectsthese safety features to work when connected to the radio.

FIG. 1 depicts an example of a simple accessory consisting of threeswitches 116 and one LED 118. In this example, the fifth GPIO, GPIO4, isunused and not shown. The physical configuration descriptor 114 iscontained in embedded memory device 120. Upon examination of FIG. 1, thefollowing port descriptors would be expected for this accessory:

GPIO 0—input, active high;

GPIO 1—input, active low;

GPIO 2—input, active low

GPIO 3—output, active low

GPIO 4—not shown and not used in this example

While priority information has not been inferred for this example, anyof the GPIO inputs can be specified as having high priority. Forexample, if GPIO 1 is a push-to-talk (PTT) switch commonly found ontwo-way radios, the GPIO 1 would likely be defined to be high priority.

After reading the physical configuration descriptor 114, the radioparses the descriptor for pin configuration information. The radio willthen configure the bi-directional GPIO interface 108 of microcontroller106 to correspond to the input or output direction specified for eachpin. For each pin that is an output, the radio configures the outputlevel to “inactive.” For example, GPIO 3 in FIG. 1 is an active lowoutput because GPIO 3 must be logic low for the LED to light. GPIO 3would thus be initialized to a logic 1 or “high” because this is theinactive state. For each pin that is an input, the radio 104 willconfigure software to monitor all inputs based on their logic type, andgenerate an activate or deactivate event on a transition. The eventtype, activate/deactivate, will be determined by the transition and thelogic type, active high or active low, assigned to each pin in thephysical configuration descriptor. The priority level of each pin willcause an interrupt configuration for high priority pins, if suchcapability is available. If accessory configuration data 124 containsmore than one physical configuration descriptor, then they areiteratively loaded and parsed.

The flexibility of the interface system 100 becomes truly apparent whenanother accessory is created using all five GPIOs of the preferredembodiment. For example, a new accessory that utilizes two LEDs andthree buttons would utilize all five of the GPIOs. For this newaccessory, suppose all three of the inputs are active low, and supposeone LED was active high and one LED was active low. Utilizing thepresent invention, no software or hardware changes are required in theradio to accommodate this new accessory, because configuration isautomatic based on the information in the physical configurationdescriptor of the new accessory. The selectable logic sense of theinterface system 100 is especially important because existingaccessories or third party accessories can easily be retrofittedeliminating re-design. Furthermore, some inputs may be sensors insteadof buttons and may have a pre-determined logic sense.

The radio will also read at least one event mapping descriptor 122 whichprovides the link between physical interface lines and actual radiofunctionality. For input events to the radio, the event mappingdescriptor determines what happens when a particular input line isactivated or deactivated. For output events from the radio, the eventmapping descriptor controls the output lines based on internal radioevents or states. In the preferred embodiment, a single mappingdescriptor contains the information for all radio events pertaining tothe accessory interface.

FIG. 2 is a block diagram of radio software architecture 200 operatingin accordance with a preferred embodiment of the invention. Radiofirmware that utilizes architecture 200 physically resides in FLASH ROM130 and also utilizes RAM 132. An accessory interface manager 202 isused to provide logical control over the interface. The accessoryinterface manager 202 is responsible for reading the embedded memorydevice containing the accessory configuration data. As stated above, theembedded memory device in the preferred embodiment is a single wiredevice, so accessory interface manager 202 uses driver 206 to access theembedded memory. The accessory interface manager 202 is also responsiblefor reading the physical configuration descriptors and event mappingdescriptors from the single wire device. This information is read andstored locally in the radio for easy access, and is shown collectivelyhere as interface configuration data 208.

The accessory interface manager 202 parses the event mapping descriptorwhich contains at least one entry. In the preferred embodiment, thereare five such entries, at least one event for each GPIO. A one-to-onerelationship between a GPIO entry in the physical configurationdescriptor and the event mapping descriptor is not required. There maybe more or less entries for event mapping. For inputs, multipleconditions may be required to trigger an event (an AND condition ofmultiple GPIOs) or different conditions could trigger the same event (ORcondition). For outputs, multiple events can also be associated with anoutput in a similar manner. Multiple events may also share a GPIO. Forexample, three GPIOs may each have a corresponding event. A fourth eventmay be defined based on the logical state of all three GPIOs. Theinformation contained for each event is specified by:

Event identifier—specifies event code in the radio

Control type—logical event or physical event

GPIO number—the GPIO related to this event

Logical event coupling—AND, OR, or NONE

Output control “toggle” or momentary duration

The event identifier specifies an event code in the radio which can be auser input or an output (indication) event. The radio softwarerecognizes the event identifier internally. Additionally, event codescan be further subdivided into logical and physical events, yielding atotal of four event types:

physical input event

logical input event

physical output event

logical output event

Logical events differ from physical events in that they convey somehigher-level logical state information about the radio. Each of thephysical input event, logical input event, physical output event,logical out event are described in more detail below.

A physical user input event specifies an activation of a physical buttonon the radio. The physical input event is detected by accessoryinterface manager 202 using accessory interface driver 204. Typically,buttons do not have pre-defined meanings. Physical buttons have buttonidentifiers which are processed by a user input manager 210. Based oninterface configuration data 208, accessory interface manager 202 knowsthe event type (logical or physical) of a given input event. Forphysical input events, accessory interface manager 202 forwards theinput event to user input manager 210. The user input manager 210 sendsdetected physical events to a user input translation task 212 which usesa translation table 214 to map the physical event to a logical event.The logical event is then forwarded to an ergonomic manager andapplications processing block 216 for processing.

A physical input event assigned to a single GPIO pin configured as aninput is therefore an external means to activate a physical radiobutton. The high level applications are unaware the “press” came overthe accessory connector, because the accessory interface manager 202sends physical user input events directly to the user input manager 210.Normal button presses on the radio itself are detected by keypad andswitch driver 218 and are also sent to user input manager 210.

If the translation table 214 were to change, then the correspondingaction of the actual radio button and the external physical input wouldalso change. This coupling may be very desirable in some cases. Forexample, referring to FIG. 3 there is shown a radio 302 and an externalmicrophone accessory 304 formed in accordance with the presentinvention. The external microphone accessory 304 includes a top button306, preferably an orange top button, similar to the radio's top button308 which may be programmed for an emergency feature. The functionalityof these two buttons 306, 308 should always be the same. By making theaccessory interface GPIO connected with button 308 associated with aphysical input event, this coupling is guaranteed. Should the userre-program this top button 306 for “phone”, the functionality of bothbuttons 306, 308 would change. The coupling in this example is desirablebecause both buttons are the same color (such as orange) and on the topof the units, and a user would expect them to behave identically. A“button mapping table” is usually stored in the radio codeplug andprovides considerable flexibility to the user in configuring a radio.

A physical output event works in a similar matter to a physical inputevent but in the reverse direction. A logical event 220, created by theergonomic manager and applications processing block 216, is sent to theuser interface task 222 which then translates this logical indicatorinto a physical indicator event 224 using translation table 215. Thistranslation table 215 maps logical events to physical hardware, sincedifferent types of radios have different types of LCD displays anddifferent type and colors of LEDs. After mapping, physical indicators224 are sent to a low level display/indicator manager 226, whichoperates the actual radio physical indicators through drivers 234. Lowlevel display/indicator driver 226 also sends physical indicator eventinformation to accessory interface manager 202. Based on interfaceconfiguration data 208, accessory interface manager 202 knows the eventtype (logical or physical) of a given output event. For physical outputevents, accessory interface manager 202 operates the associated GPIOline in accordance with the output event using accessory interfacedriver 204.

An accessory interface port configured as an output and having aphysical output event associated with it would function exactly like aphysical indicator on the radio. An example would a microphone accessorywith a red LED indicator. Using a physical output event causes the redLED to work just like the radio's red LED. The red LED indicates atransmit condition, and depending on the radio, it might also indicatelow battery and busy channel conditions. A physical output event mightalso be used to add a new indicator not physically present on the radio.For example, an external microphone with a tactile transducer (vibrator)can be connected to the radio. The radio may already know about thistype of indicator and how to process it, but this indicator may not bephysically realized on the radio. By adding the vibrating microphone,the new indicator automatically works because the accessory interfacemanager 202 will route this physical indicator to the vibrator's signalline.

For physical events the accessory interface manager 202 reads both thephysical configuration descriptors and the event mapping descriptors(from interface configuration data 208) and then determines the logicnecessary to manage these events. For input events, including both thedetection and “undetection” of the event, the accessory interfacemanager 202 sends the physical event 230 to the user input manager 210.For output events, the accessory interface manager 202 monitors physicaloutput events 236 from the low level display/indicator manager 226 andactivates/deactivates the appropriate lines to display and indicatordrivers 234.

The logical events coupling field for each event in the event mappingdescriptor specifies whether this event is coupled to other events.Logical event coupling can apply to physical and logical events. Thismechanism allows multiple lines to trigger one physical input event orone physical output event to trigger multiple lines. As an example,consider the external microphone 304 of FIG. 3 that has a PTT switch310, hang up box (HUB)/monitor 312, a phone button 314, and the orangebutton 306. Three entries are made in the physical configurationdescriptor, one for each of the three GPIO lines (GPIO 0, GPIO 1, GPIO2) connected to the first three of these buttons. The fourth button, theorange button, 306 is connected to GPIO 0 and GPIO 2 (PTT and phone).Three entries are also made in the event mapping descriptor, one foreach of the first three buttons.

Event identifier—2101 (physical—PTT)

Event type—input event

Control type—physical event

GPIO number—GPIO 0

Logical coupling—none

Output control—not applicable (this field for output events only).

Event identifier—2107 (physical—monitor/hub)

Event type—input event

Control type—physical event

GPIO number—GPIO 1

Logical coupling—none

Output control—not applicable (this field for output events only).

Event identifier—2140 (physical—phone)

Event type—input event

Control type—physical event

GPIO number—GPIO 2

Logical coupling—none

Output control—not applicable (this field for output events only).

Two additional entries are added for the fourth button. The entries areshown below:

Event identifier—2133 (physical—orange button)

Event type—input event

Control type—physical event

GPIO number—GPIO 0

Logical coupling—AND

Output control—not applicable (this field for output events only).

Event identifier—2133 (physical—orange button)

Event type—input event

Control type—physical event

GPIO number—GPIO 2

Logical coupling—AND

Output control—not applicable (this field for output events only).

The descriptor information above shows that a “physical orange button”event will occur when both the GPIO 0 and GPIO 2 are active. Theaccessory interface manager 202 is responsible for detecting andunderstanding these logical relationships and handing the eventprocessing associated with them.

The processing for logical input or output events is similar to theprocessing for physical ones. The same relational operator can alsoapply to logical events. Again, logical events differ from physicalevents in that they convey some state information about the radio. Thisstate information may or may not be physically conveyed otherwise. Forexample, a logical input event “enter emergency” would cause the radioto activate the emergency feature and enter the emergency state. In aprevious example on physical input event, an orange button on anexternal microphone was specified which aligns with the orange buttoncommonly found on portable radios. In this previous example, thefunctionality of the two buttons was always the same because it was aphysical input event. The two physical inputs—one on the radio and oneon the microphone—would be combined for later translation. In thelogical input event example, a button could be specified to have alogical event called emergency associated with it. Because this is alogical input event, this button will always be emergency regardless ofthe radio connected to the microphone and regardless of any buttonmapping in the radio codeplug (assuming the connected radio contains theemergency feature).

For a logical output event case, referring again to FIG. 3, a microphone304 with a green LED 332 may be associated with a “call alert received”logical event. When the radio receives a call alert this event isactivated. On most portable radios, a call alert is indicated by ablinking green LED 330. If a physical output event was used in thisexample instead of a logical one, the green LED 332 would similarly beactivated when a call alert was received. But because of a physicalmapping, the microphone green LED 332 would also be activated on phonereceived, private call received, and others. If a green LED is desiredfor a call alert received and phone call received only, then two logicalevents can be set up in the event mapping descriptor using an ORrelationship. Both entries can map to the same GPIO, which is connectedto the green LED 332.

For logical events the accessory interface manager 202 reads both thephysical configuration descriptor and the event mapping descriptors andthen determines the logic necessary for these events. For input events,including both the detection and “undetection” of the event, theaccessory interface manager 202 sends the logical event 240 directly tothe high level ergonomic manger and application processing block 216.For output events the, the accessory interface manager monitors logicaloutput events 242 from the high level and takes appropriate action.Because of the complexity of today's tow-way radios and the potentiallylarge number of logical events, a registration service is used in thepreferred embodiment. Upon detection of an accessory, the accessoryinterface manager knows which logical events, if any, must be monitored.The manager then registers the desired events with the ergonomic managerand application processing block 216 for the events of interest. In thismanner, only relevant events are received by the accessory interfacemanager. Registered events are stored in event subscription list 232 ofFIG. 2.

For logical output events, an additional field for each event in theevent mapping descriptor specifies “output control.” If this field isset to “toggle,” then the signal will reflect whether a radio is in aparticular state. A transition will occur when the event happens, and anopposite transition will occur when the event is reset (the radio hasexited the state that caused the event). If the field is set tomomentary duration, then a pulse will be output upon detection of theevent. The pulse duration is configurable in the descriptor. An exampleof the toggle control would be a qualified channel activity receiveindication. The output signal would be “active” for the duration of thequalified channel activity. An example of the toggle momentary durationwould be an emergency indicator intended to trigger another device. Theemergency indicator can be configured for a 500 ms pulse, for example.The terms “active” and “inactive” are used to describe the state of thesignals because the physical configuration descriptor allows active highor active low logic on a per-GPIO basis.

As demonstrated by the preceding examples, the interface system of thepresent invention provides significant flexibility in signal routing andcoupling to high-level and low-level radio events. In accordance withthe present invention, the addition of accessory interface manager 202,accessory interface driver 204, interface configuration data 208, eventsubscription list 232 and input/output event paths 230, 236, 240, 242provide expanded accessory interfacing and configuration capability. Anumber of other extensions and modifications can further enhance theinterface system of the present invention. For example, the physicalconfiguration descriptors or event mapping descriptors can be encryptedor digitally signed to restrict operation of the interface to approvedaccessories. When the accessory interface manager reads thesedescriptors it decrypts or authenticates them. Improperly signeddescriptors will prevent interface configuration, rending the accessoryinoperable. While described primarily in terms of digital signals, theinterface system can be extended to include analog inputs and triggerthresholds. Periodic polling can be used to support various sensors ifdesired. While the preferred embodiment has described the logicalcoupling in terms of AND conditions or OR conditions to be used to linkentries in the event mapping descriptor, more complex logic could beused along with other implantations to implement the logical coupling.

Accordingly, there has been provided an interface system that provides aconfigurable interface by storing physical signal configurationinformation in a memory device in an accessory. The information iscoupled to event processing information that is also specified in thememory device. New accessories can now be deployed with no changes tothe physical interface or the radio software. While the description hasreferred to a portable radio, the interface system of the presentinvention applies equally to a mobile radio. The interface system formedin accordance with the present invention provides a highly flexiblemeans to interface accessories of varying complexity to portablecommunication devices. Future accessories can now be affordedcapabilities not previously available or previously available only to“smart” accessories. These accessories can now be deployed with enhancedor altered capabilities with no change to the radio software or hardwarekeeping the devices small and pin counts low.

While the preferred embodiments of the invention have been illustratedand described, it will be clear that the invention is not so limited.Numerous modifications, changes, variations, substitutions andequivalents will occur to those skilled in the art without departingfrom the spirit and scope of the present invention as defined by theappended claims.

1. An interface system, comprising: a portable communication devicehaving a configurable external interface; an accessory having a memorywith accessory configuration data stored therein in the form of physicalconfiguration and event mapping descriptors pertaining to the accessory,the accessory having no microcontroller; and portable communicationdevice software in the portable communication device for reading thedescriptors and configuring the configurable external interface inresponse thereto.
 2. An interface system, comprising: a radio having aconfigurable external interface; at least one accessory compatible withthe configurable interface and containing at least one memory devicehaving accessory configuration data stored therein in the form ofdescriptors; at least one physical configuration descriptor stored inthe accessory containing interface configuration information for thataccessory; at least one event mapping descriptor stored in the accessorycontaining event mapping information for the interface of thataccessory, the at least one physical configuration descriptor and the atleast one event mapping descriptor being stored as data in the at leastone memory device of the at least one accessory; radio software in theradio for reading the interface configuration information and the eventmapping information contained in the descriptors, and configuring theconfigurable external interface and processing events without the use ofany microcontroller within the accessory.
 3. The interface system ofclaim 2, wherein the physical configuration descriptor interfaceconfiguration information includes data direction, logic sense, andpriority.
 4. An interface system for coupling a radio having an externalradio interface to an accessory, comprising: at the radio: amicrocontroller having a configurable general purpose input output(GPIO) interface connected to the external radio interface, the GPIOinterface being configured as an input device upon radio power-up, andthe radio periodically checking the external radio interface to detectthe presence of an accessory; at the accessory: a single wire memorydevice containing accessory configuration data in the form of eventmapping and physical configuration descriptors providing informationabout the accessory without any microcontroller within the accessory;and upon accessory detection by the radio microcontroller, the radioreads the event mapping and physical configuration descriptors of thesingle wire memory device and configures the external radio interface inresponse thereto.
 5. The interface system of claim 4, wherein the GPIOcomprises an extended GPIO to limit the interface system topredetermined accessories.
 6. An interface system, comprising: a radiohaving a microcontroller with bi-directional general purpose inputoutput (GPIOs) and an external radio interface; a plurality ofaccessories without microcontrollers each having accessory configurationdata in the form of physical configuration descriptors and event mappingdescriptors stored therein and each having an external accessoryinterface; and the external radio interface automatically beingconfigured via the radio microcontroller to each external accessoryinterface based on the physical configuration and event mappingdescriptors of each of the plurality of accessories.
 7. The interfacesystem of claim 6, wherein the physical descriptors provide logic highsand lows to the GPIOs.
 8. The interface system of claim 6, wherein theradio modifies performance of an accessory from the plurality ofaccessories based on the physical descriptor of that accessory, by theradio selectively controlling the logic of the GPIOs.
 9. The interfacesystem of claim 6, wherein the radio rejects an accessory from theplurality of accessories based on the physical descriptor of thataccessory.
 10. An interface system for an accessory and communicationdevice, including: a memory device in the accessory, the memory devicehaving accessory configuration data in the form of a physicalconfiguration descriptor and an event mapping descriptor stored therein,the physical configuration descriptor and event mapping descriptor forconfiguring the interface system without a microcontroller in theaccessory via the communication device.
 11. The interface system ofclaim 10, wherein the physical configuration descriptor and the eventmapping descriptor configuring the interface system allow for variousaccessories to be coupled to the communication device.
 12. The interfacesystem of claim 10, wherein the memory device having accessoryconfiguration data has no radio device driver or executable code storedtherein.